静力弹塑性分析方法中不同加载模式的对比研究  

Comparative Study on Different Load Pattern in Pushover Analysis Method

作　　者：李家青[1] 

机构地区：[1]江苏省建筑科学研究院有限公司,江苏南京210008

出　　处：《江苏建筑》2009年第4期36-40,共5页Jiangsu Construction

摘　　要：Pushover分析方法是一种逐渐得到广泛研究与应用的评估结构抗震性能的简化方法,已经被我国现行建筑结构抗震设计规范采用。侧向加载模式的选取是Pushover分析方法中的一个关键问题,不同结构的高阶振型对Pushover分析结果的影响程度不同。本文通过拟合规范的反应谱曲线,对三个钢筋混凝土结构分别选取了适用Ⅱ类场地的2条地震动记录和1条人工波,对比了典型地震动下非线性时程分析和采用5种不同侧向力分布模式的Pushover分析的层间位移角,以及推覆分析各工况下的结构推覆曲线、等效周期和等效阻尼比。通过振型质量参与系数体现高阶振型对结构反应的贡献。研究发现,随着结构层数的增加,高阶振型的影响变大,侧向加载模式的选取变得很重要。Pushover analysis is a simplified method for structure seismic evaluation, which is extensively studied and used gradually,and is adopted by the current code of seismic design of buildings.The lateral load pattern selection is one of the critical issues in pushover analysis, the higher modes of different structures have different effect extent.In this paper,by fitting the norm response spectrum, two natural earthquake records and one artificially generated acceleration record which are fit for the second soil site are separately selected for three RC buildings.Comparison of story drift between nonlinear time history analysis （NL-THA）employing typical earthquake records and pushover analysis using five different load patterns is undertaken.Pushover curves, equivalent period and equivalent damping ratio are contrasted under the cases of pushover analysis.By modal mass participation factors,the influence of higher modes is embodied.It is found that with the increase of floor, the higher modes influence is getting important and the selection of lateral load pattern becomes very important.

关 键 词：静力弹塑性分析方法 推覆分析 侧向加载模式 结构目标位移 

分 类 号：TU313[建筑科学—结构工程]